"The club would like to express its appreciation of Garrido's work during his time in charge. Luck was not on his side though as the results did not match the hopes and expectations of the fans," Ismaily said in a statement.
"Ayman El-Gammal will take charge of the first team on an interim basis."
Ismaily, who escaped relegation in the latter stages of last season, were eyeing a fresh start after naming Garrido as their new boss in the summer.
They also signed a handful of new players but still made a poor start to the season, drawing twice and losing three times in their opening five games.
They lie third from bottom with only two points, two adrift of the safety zone.
Garrido's second Egyptian spell has now come to an end. The 53-year-old was in charge of Cairo giants Ahly in the 2014-15 season, leading them to an African Confederation Cup triumph but losing the Champions League and domestic league titles.
(For more sports news and updates, follow Ahram Online Sports on Twitter at @AO_Sports and on Facebook at AhramOnlineSports.)